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List Of Prehistoric Nautiloid Genera
This list of nautiloids is a comprehensive listing of all genera that have ever been included in the subclass Nautiloidea, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (''nomina dubia''), or were not formally published ('' nomina nuda''), as well as junior synonyms of more established names, and genera that are no longer considered nautiloids. Most of the listed genera are found in Part K of the ''Treatise on Invertebrate Paleontology''. Some, added since the year of publication (1964) are found simply in various scientific journals and special publications. The named genera are based on type specimens which are housed in various museums and other academic institutions worldwide, available to interested researchers. Note that '' Allonautilus'' and '' Nautilus'' are the only extant genera. A *†'' Acanthonautilus'' *†'' Acaroceras'' *†''Acleistoceras'' *†'' Acrosphaerorthocera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adelphoceras
''Adelphoceras'' is a genus of middle Devonian coiled nautiloids from Europe with an oval whorl section and shallow depressed zone on the inner, dorsal, rim; a strongly contracted T-shaped aperture; ventral siphuncle containing actinosiphonate deposits, and two rows of spines on either side. ''Adelphoceras'' is included in the nautilid family Rutoceratidae Rutoceratidae is a family of prototypical nautilids, derived probably from either Brevicoceratidae or Acleistoceratidae of the order Oncocerida early in the Devonian. Rutoceratidae comprise a family within the oncocerid superfamily Tainocerat ..., and is also a part of the Tainoceratoidea. References * Bernhard Kummel, 1964. Nautiloidea - Nautilida. Treatise on Invertebrate Paleontology, Part K. Geological Society of America and University of Kansas Press. Prehistoric nautiloid genera Fossil taxa described in 1870 {{paleo-nautiloidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aletoceras
''Aletoceras'' is a genus of Oncocerida nautiloids from the middle Devonian of North America included in the family Brevicoceratidae. The shell is a depressed brevicone, that is to say short. Sutures are generally straight, the siphuncle ventral, empty. The peristome (aperture rim) has a broad hyponomic sinus -for the hydrojet funnel, ventrolateral projections, dorsolateral sinuses - possibly for the eyes, and probably a mid dorsal sinus. In general form, ''Aletoceras'' resembles '' Brevicoceras'' and '' Eleusoceras'', both also from the middle Devonian of North America. The orientation of ''Aletoceras'' and others like it may have been vertical with the aperture facing down . References * W.C. Sweet 1964. Nautiloidea - Oncocerida, Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albertoceras
''Albertoceras'' is a genus of Early Ordovician ellesmeroceratids with a small, slender, orthoconic to slightly endogastric shell; some even tiny. The cross section is strongly compressed so as to make the height proportionally notably greater than the width. The sutures, marking the edges of the septa, have broad, shallow, lateral lobes. The siphuncle, which seems to lack diaphragms, lies close to the venter. ''Albertoceras'' differs from ''Ectenolites'', which it closely resembles in the early, or juvenile, portion, in having a short living chamber that narrows toward the aperture and a convex dorsal profile in the adult portion. The ventral profile remains straight throughout. ''Albertoceras walcotti'', the type species, and ''A. gracillimum'' are both from the Mons Formation of Alberta. ''A. staufferi'' is from the Tanyard Formation of Texas and ''A. clelandi'' is from the Tribes Hill Limestone of New York. References * R.H. Flower, 1964. The Nautiloid Order Ellesmerocer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaskoceras
''Alaskoceras'' is a genus of lower Ordovician coiled nautiloid cephalopods; the shell moderately expanded, ribbed, with a divergent living chamber; whorl section more broadly rounded ventrally than dorsally; siphuncle marginal at maturity, septal necks short, almost achoanitic; connecting rings thick, layered. ''Alaskcoceras'' belongs to the Tarphycerida The Tarphycerida were the first of the coiled cephalopods, found in marine sediments from the Lower Ordovician (middle and upper Canad) to the Middle Devonian. Some, such as '' Aphetoceras'' and '' Estonioceras'', are loosely coiled and gyroconi ..., and to the family Estonioceratidae. It was found in Alaska. References * W.M Furnish & Brian F. Glenister, 1964. Nautiloidea-Tarphycerida. Treatise on Invertebrate Paleontology, Part K. Geological Society of America and University of Kansas Press. Ordovician cephalopods of North America Prehistoric nautiloid genera {{paleo-nautiloidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aktjubocheilus
''Aktjubocheilus'' is a genus of oncocerid nautiloids from the Upper Devonian (M Famenian) included in the Acleistoceratidae, a family characterized by depressed, or rarely compressed, exogastric brevicones and cyrtocones. References The Paleobiology Database ''Aktjubocheilus'' entryaccessed 8/21/12 Sepkoski J.J. List of Cephalopod Genera* Walter c. Sweet, 1964 Nautiloidea - Oncocerida. ''Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and co ...'', Part K, 1964. Prehistoric nautiloid genera {{paleo-nautiloidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aipoceras
''Aipoceras'' is a genus of loosely coiled aipoceratid nautiloid Nautiloids are a group of marine cephalopods ( Mollusca) which originated in the Late Cambrian and are represented today by the living ''Nautilus'' and ''Allonautilus''. Fossil nautiloids are diverse and speciose, with over 2,500 recorded species ...s with laterally compressed whorls; shells expanding moderately to fairly rapidly with a tendency to uncoil at maturity. Juvenile forms are somewhat cyrtoconic. The apical end forms a hook. ''Aipoceras'' has been found in Lower Mississippian strata in the U.S. References * Bernard Kummel, 1964. Nautiloidea - Nautilida; Treatise on Invertebrate Paleontology. Geological Society of America.''Aipoceras''iFossilworks Prehistoric nautiloid genera Fossil taxa described in 1884 {{paleo-nautiloidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
